Thermodynamical Bethe Ansatz analysis in an SU(2)xU(1) symmetric sigma-model

Janos Balog; Peter Forgacs

doi:10.1016/s0550-3213(99)00754-3

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arXiv · hep-th/9906007

Thermodynamical Bethe Ansatz analysis in an SU(2)xU(1) symmetric sigma-model

Janos Balog·Peter Forgacs

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Abstract

Four different types of free energies are computed by both thermodynamical Bethe Ansatz (TBA) techniques and by weak coupling perturbation theory in an integrable one-parameter deformation of the O(4) principal chiral sigma-model (with SU(2)xU(1) symmetry). The model exhibits both `fermionic' and `bosonic' type free energies and in all cases the perturbative and the TBA results are in perfect agreement, strongly supporting the correctness of the proposed S matrix. The mass gap is also computed in terms of the Lambda parameters of the modified minimal substraction scheme and a lattice regularized version of the model.

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Janos Balog, Peter Forgacs. 1999-12-29. Thermodynamical Bethe Ansatz analysis in an SU(2)xU(1) symmetric sigma-model. https://doi.org/10.1016/s0550-3213(99)00754-3

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